▼ This work introduces a vision-based target-tracking system for small, rotary-wing drones. Recent advances in computer vision algorithms, parallel processing, and low-power computer architecture make autonomous target tracking with small unmanned aerial vehicles (UAVs) a distinct possibility. I implement an onboard tracking module for a rotary wing UAV. The tracking algorithm used is capable of tracking arbitrarily defined targets, a feature that I have not found in previous onboard target-tracking devices.
I implement two tracking algorithms for the module and compare their performance. One is a so-called ???feature-based??? tracker while the other uses a convolutional neural network. The results show that the neural-network-based method out-performs the feature-based method, but runs too slowly for a real-time application. The faster feature-based implementation processes over 10 frames per second, which makes the module a feasible solution for real-time tracking.
Advisors/Committee Members: Raheja, Amar (advisor), Bhandari, Subodh (committee member).

▼ Tämän opinnäytetyön tarkoituksena oli tarkastella multikopterin lennonohjaustietokoneelle tehdyn laiteohjelmiston suunnitteluun liittyviä asioita. Laiteohjelmiston pohjana toimi avoimen lähdekoodin FreeRTOS-reaaliaikakäyttöjärjestelmä. Laiteohjelmiston testaus tapahtui tarkoitusta varten rakennetussa lennonohjaustietokoneessa, joka asennettiin neliroottoriseen multikopteriin.
Työssä tutkittiin multikopterien ohjausmenetelmiä. Radio-ohjauselektroniikasta tuttua pulssinleveyden modulaatioon perustuvaa signaalia käytettiin yhdistämään lennonohjaustietokone multikopterin muihin komponentteihin. Lennonohjaustietokoneen antureita ja radiovastaanottimelta tulevaa ohjausta hyödynnettiin PID-säätimissä, joiden on tarkoitus vakauttaa multikopterin lento. Antureiden mittaustulokset yhdistettiin anturifuusiolla käyttäen Complementary-suodinta. Säätimiä ja anturifuusiota käytettiin eri ohjaustiloissa, jotka määrittävät sen, miten multikopterin lennonohjausjärjestelmä toimii. Lennonohjausjärjestelmän toiminnan reaaliaikaisuus todettiin mittaamalla käyttöjärjestelmän suoritus- ja vasteajat.
Opinnäytetyön avulla saatiin tietoa muun muassa säätötekniikasta, anturijärjestelmistä, anturifuusiosta, radio-ohjauksesta ja telemetriasta. Etenkin tietoa saatiin näiden kaikkien osa-alueiden soveltamisesta laiteohjelmistossa, jonka perustana on reaaliaikakäyttöjärjestelmä. Tämän opinnäytetyön tekemisessä syntyneitä ideoita on tarkoitus hyödyntää lennonohjausjärjestelmän jatkokehityksessä. Niistä voi olla hyötyä myös muun tyyppisten sulautettujen järjestelmien ja näiden laiteohjelmistojen kehityksessä, jotka ovat riippuvaisia samoista teknologioista.; The purpose of this bachelor’s thesis was to study the design and implementation of a firmware for a multirotor flight control computer. The firmware of the flight control computer was based on FreeRTOS, an open source real-time operating system. The testing of the software was done in a purpose built flight control computer, which was installed on a quadcopter.
The control methods of a multirotor were studied. Pulse-width modulation, a technique that is used frequently in radio-controlled electronics, was utilized to interconnect the components of the multirotor. The sensors on the flight control computer and the control signal from the radio-control receiver were utilized in PID-control algorithm, to stabilize the flight of the multirotor. Sensor data was combined using Complementary filter, a sensor fusion algorithm. The combinations of control and sensor fusion algorithms were used to create different flight control modes. The flight control modes define how the flight control system operates. Real-time operation of the flight control system was verified by measuring the execution and response times of the operating system.
This thesis provides information about control technology, sensor systems, sensor fusion, radio-control and telemetry. Information was obtained particularly about the combination of all these technologies in a firmware, which is based on a real-time operating…

UAS has been become a very popular tool in surveying and evaluation of the systems measurement uncertainties are necessary. The most common method for…
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UAS has been become a very popular tool in surveying and evaluation of the systems measurement uncertainties are necessary. The most common method for georeferencing UAS data is to use ground control points (GCP) in order to use them in block adjustment. In recent years’ new techniques for direct georeferencing with UAS have been presented, which in theory means that the position of the UAS can be determined accurately enough and therefore GCP’s can be excluded. This study evaluates uncertainties of the UAS Freya from SmartPlanes that don’t need GCP’s for georeferencing. The technique applied in the evaluation is based on Post Processed Kinematic (PPK) for coordinate determination of the UAS, which means that the collected GNSS data can be post processed using a reference station. The test area was a 280 x 320 m block in the north end of Gävle airport, Sweden. Each flight is conducted in two orthogonal blocks and evaluated in three different ways against the 16 GCP. The altitude was about 90 m for all flights. The uncertainty of the PPK-technique is tested and evaluated with three different methods to ensure both accuracy and potential use. In total five flights were assessed and evaluated with Agisoft PhotoScan against 16 GCP spread over the area. The position of each GCP’s was determined with four independent network RTK measurements. The results show that the georeferencing with the PPK-technique and block adjustment has potential to meet the uncertainties in level with indirect georeferencing using GCP. The results show very similar planimetric uncertainties, around 0,020 m in RMS, for all evaluations with the PPK-technique. The results of the uncertainty in height is more scattered where the two lowest results in a RMS under 0,015 m and the highest over 0,100 m for the difference against the 16 GCP. It is possible to achieve low uncertainties with the method without the use of GCP. For areas where establishment of GCP is not possible, using UAS equipped with PPKtechnology provides a very suitable alternative to use. The results show relatively large differences between the evaluations and in order to determine the exact cause of them, further studies are required.

► The field of robotics and mechatronics is advancing at an ever-increasing rate and we are starting to see robots making the transition from the factories…
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▼ The field of robotics and mechatronics is advancing at an ever-increasing rate and we are starting to see robots making the transition from the factories to the workplace and homes as cost is reduced and they become more useful. In recent years quadrotors have become a popular unmanned air vehicle (UAV) platform. These UAVs or micro air vehicles (MAV) are being used for many new and exciting applications such as aerial monitoring of wildlife, disaster sites, riots and protests. They are also being used in the film industry, as they are significantly cheaper means of getting aerial footage. While quadrotors are not extremely expensive a good system can cost in the range of 3000 - 8000 and thus too costly as a research platform for many. There are a number of cheaper open source platforms. The ArduCopter is under constant development, has the largest community and is inexpensive making it an ideal platform to work with. The goal of this thesis was to implement video processing on a ground control station allowing for the ArduCopter to track moving objects. This was achieved by using the OpenCV video-processing library to implement object tracking and the MAVLink communication protocol, available on the ArduCopter platform, for communication.
Advisors/Committee Members: Kougianos, Elias, Mohanty, Saraju P., Foster , Phillip, Nasrazadani, Seifollah.

Coelho, G. (2012). Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition. (Thesis). University of North Texas. Retrieved from https://digital.library.unt.edu/ark:/67531/metadc115056/

Note: this citation may be lacking information needed for this citation format:Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Coelho, Gavin. “Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition.” 2012. Thesis, University of North Texas. Accessed May 25, 2019.
https://digital.library.unt.edu/ark:/67531/metadc115056/.

Note: this citation may be lacking information needed for this citation format:Not specified: Masters Thesis or Doctoral Dissertation

Coelho G. Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition. [Internet] [Thesis]. University of North Texas; 2012. [cited 2019 May 25].
Available from: https://digital.library.unt.edu/ark:/67531/metadc115056/.

Note: this citation may be lacking information needed for this citation format:Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Coelho G. Ota-quadrotor: An Object-tracking Autonomous Quadrotor for Real-time Detection and Recognition. [Thesis]. University of North Texas; 2012. Available from: https://digital.library.unt.edu/ark:/67531/metadc115056/

Note: this citation may be lacking information needed for this citation format:Not specified: Masters Thesis or Doctoral Dissertation

► This thesis reports on a conceptual design of a solar-powered unmanned aerial vehicle (UAV) with a mass no more than 10 kg. This UAV…
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▼ This thesis reports on a conceptual design of a solar-powered unmanned aerial vehicle (UAV) with a mass no more than 10 kg. This UAV will have the necessary equipment to study wildfires in California, including a Global Positioning System (GPS) and infrared cameras. Using similar aircraft in the same weight class, the geometry of the aircraft was calculated. A weight analysis and a power sensitivity analysis indicated that this aircraft will generate 350 W of power, 114.6 W greater than the power available to fly. A stability and controls analysis was also done, and the required tail area needed for stability was calculated. Using XFLR5, which is a software package that studies aerodynamic properties, a drag polar estimate was calculated and compared with basic aircraft design methods to verify the accuracy of the results.

The radar cross-section (RCS) is a key parameter used to determine whether or not an airborne target will be detected by a radar at a…
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The radar cross-section (RCS) is a key parameter used
to determine whether or not an airborne target will be detected by
a radar at a given range. The accurate measurement of the RCS is of
particular importance for the detection of miniature unmanned
aerial vehicles (UAV) because the radar return strength is low.
Although the UAV's RCS may be determined statically in an anechoic
chamber, it may be advantageous to measure it whilst the target is
in motion due to the greater resemblance with an operational
environment. However, the dynamic measurement of RCS adds
complexity to the measurement system because of the requirement to
track the UAV in-flight. Furthermore, vibrations and moving parts
modulate the return echo, which implies that the RCS can only be
characterized statistically.
This work describes the design of
the Dynamic RCS Measurement System used to measure the RCS of UAVs
flying indoors. The results of measurements of a test UAV and
comparison with static measurements show that the Dynamic RCS
Measurement System is a viable option to investigate how dynamic
effects affect the RCS of a flying UAV and to compute probabilities
of detection.

Project Solaris is a student research project with the goal to build a solar powered Unmanned Aerial Vehicle. This study is one in a…
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Project Solaris is a student research project with the goal to build a solar powered Unmanned Aerial Vehicle. This study is one in a set of studies that make up the initial phase of project Solaris. The main objective of this report is to investigate earlier solar powered airplanes as well as evaluate (or explore) potential future niche markets where solar powered UAVs could excel.A presentation of earlier solar powered airplanes will give an overall understanding of how solar powered airplanes have evolved and also provide information about the goals and ambitions behind the projects.Potential applications such as power line inspection and algal bloom observation will be described and a list of specifications for each application will be presented.

► The purpose of this research was to design a multiple UAV system with collaborative operation. This project is built on work that has been done…
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▼ The purpose of this research was to design a multiple UAV system with collaborative operation. This project is built on work that has been done in the field of Unmanned Systems at VCU and is aimed at providing a starting point for research into collaborative control of multiple UAVs. The current GCS software was extended to include multiple vehicles per single controller via a new communication protocol. Many changes were made to the user interface to facilitate controlling multiple vehicles with a single operator. A second processor, called an MCS, was added to each vehicle to allow for greater flexibility and processing power, while maintaining backwards-compatibility and limiting infringement on the real-time processing of the FCS itself. The system was fully simulated via both hardware and software simulators, and ultimately the system was field tested using multiple vehicles collaboratively searching a defined area.
Advisors/Committee Members: Dr. Robert H. Klenke.

► The emergence of unmanned aerial vehicles and the ever increasing performance in terms of speed, flight altitude, and endurance have led the debate into allowing…
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▼ The emergence of unmanned aerial vehicles and the ever increasing performance in terms of speed, flight altitude, and endurance have led the debate into allowing such aircraft to fly co-jointly with civilian aircraft. However, due to the absence of the usual flight regulation channel, not to mention the pilot at the aircraft controls, the need for an automated collision avoidance system has arisen in the past few years.
For that we propose to provide a practical solution to equip UAVs with an autonomous sense and avoid capability and an autonomous collision avoidance system, to enable the UAV to fly in a non segregated air space safely and meeting the above regulations.
In this research, we have evaluated different types of mechanism to form this collision avoidance system. The most successful of which concluded of path estimation and the calculation of nearest point of approach. During this research, we developed a collision avoidance mechanism that uses vector algorithms and path estimation methods to increase the efficiency of the logic system and decrease the computation time.
In the results of this experiment, we determined that using few well developed manoeuvres would result in better avoidance efficiency and would require limited change to the flight path of the unmanned vehicle and flight parameters.
Manoeuvres such as changing speed or turning provided the best options for avoiding incoming aircraft, while changing altitude was less successful due to the danger of flying into a different flight level (sharing the same altitude levels with other aircraft) and due to the limited climb and decent rate performances of the model unmanned aerial vehicle used.
More complicated scenarios, such as avoiding multiple aircraft would require a slightly different strategy, where the algorithm would be based upon avoiding a flight path of all aircraft at all times, rather than changing velocity or heading to avoid colliding at a certain point in time.
The main outcome of this experiment, was to prove that such algorithms (with limited complex theory behind it) can prove to be a good option for deriving avoidance systems and ensuring flight safety for manned and unmanned aircraft.
Testing was successfully conducted by the student on simple implementation of the Loss of Separation algorithm to verify, test and expand the algorithm as a pre-preparation for code integration in later
stages.
In this document, we present how we will implement the “sense and avoid” algorithm and the logical decision making system that would provide the UAV with the ability to re-route its current path to a safer flight course.
Advisors/Committee Members: Collins, John (advisor).

► Small unmanned aircraft are being used in an increasing number of applications ranging from emergency response to parcel delivery. Many of these applications are benefited…
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▼ Small unmanned aircraft are being used in an increasing number of applications ranging from emergency response to parcel delivery. Many of these applications are benefited when employed as a multiple-vehicle operation. Such operations often require tight cooperation between heterogeneous vehicles and often depend on integration with sensors and payloads. Multi-agent control algorithms can be implemented to control such systems but often require the development of an underlying vehicle communications framework in addition to a sensors and payloads communications framework. This thesis presents a single unified modular framework, named Clark, and supports heterogeneous multi-agent control and sensor/payload integration. Clark provides a wireless network between agents without relying on pre-existing communications infrastructure, and provides software interfaces for connecting to a variety of payloads. This thesis first reviews small unmanned aircraft systems (SUAS), multi-agent control, multi-agent control testbeds, and wireless networking technologies used on SUAS. Systems engineering is then employed to develop an Identified Need, Concept of Operations (ConOps), and requirements. All Defined, Derived, and Design Requirements are explained and justified. Some requirements are highlighted to demonstrate key features of the Clark framework. The software architecture is explained in detail in a top-down approach. Hardware is selected for prototyping and shown to meet the requirements. Bench tests, ground tests, and flight tests are conducted to verify the framework?s ability to communicate between agents and affect control. Ground testing includes a multi-agent cooperative mission while flight testing features two and three agent missions. Test results are presented and demonstrate the candidacy of Clark as a modular heterogeneous multi-agent control framework with integrated payloads.
Advisors/Committee Members: Valasek, John (advisor), Huff, Gregory H (committee member), Benedict, Moble (committee member), Kumar, P. R. (committee member).

► Unmanned aerial vehicles are seeing increasing use in a variety of applications including warfare, imaging, communication, search and rescue, meteorology, agriculture, and more. For most…
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▼ Unmanned aerial vehicles are seeing increasing use in a variety of applications including warfare, imaging, communication, search and rescue, meteorology, agriculture, and more. For most applications, flight endurance on the order of days, weeks, or even years is desirable. Photovoltaic cells represent an emerging and viable method of powering unmanned aerial vehicles on such long endurance flights. This study investigates the design optimization of a small solar powered unmanned aerial vehicle. The aircraft is intended to weigh less than twenty pounds and to fly for 24 hours at low altitude over Sacramento, California during the summer months of May through September. Photovoltaic technology and the characterization of a thin-film photovoltaic cell are reviewed. The majority of the paper describes the methods used to implement a continuous design approach in which the battery pack power, photovoltaic efficiency, and aircraft weight were determined for a given aspect ratio and wing loading. The optimum aspect ratio and wing loading to minimize both battery pack power and photovoltaic efficiency are identified and the final design is discussed. The results indicate that aspect ratio exhibits a strong inverse relationship with aircraft weight, wing loading is directly related to minimum required photovoltaic efficiency, and that minimum aircraft weight does not translate to minimum power required.
Advisors/Committee Members: Tuzcu, Ilhan.

► In the following paper, the process of identifying benefits and problems of 3D printing with respect to small, autonomous aircraft is detailed. This serves as…
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▼ In the following paper, the process of identifying
benefits and problems of 3D printing with respect to small,
autonomous aircraft is detailed. This serves as a proof-of-concept
that such an UAV can be fabricated with minimal requirements on
skill and labor in small labs equipped with 3D printers, as well as
the option of rapid incorporation of modifications to the airframe.
The problems introduced by 3D printing are the relatively heavy
airframes required by the materials, large tolerances involved, and
an inherent internal weakness in one direction of every part.
Nevertheless, the design presented has been proven to have stable
and controllable flight characteristics and a very short assembly
process. It has already undergone substantial iteration based on
both empirical data from flight testing and from simulation
software. This has resulted in an aircraft that can be launched by
multiple methods, is optimized for a low speed loiter mission, and
has a significant amount of damage tolerance and
payload.
Advisors/Committee Members: Haj-Hariri, Hossein (advisor).

► This project acquired high-resolution, RGB images of a deciduous forest in Athens, Ohio from an unmanned aerial vehicle over the course of a year. With…
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▼ This project acquired high-resolution, RGB images of a
deciduous forest in Athens, Ohio from an unmanned aerial vehicle
over the course of a year. With UAVs, greater temporal and spatial
scales exist today than what were available in the recent past with
the full capabilities of these images yet to be fully assessed. The
goal of the project was to follow the different phenology patterns
of various deciduous trees to accurately map the project site while
formulating a reproducible methodology for future work. Acquiring
mosaics for 29 dates in 2017, a supervised Maximum Likelihood
Classification scheme was employed to classify various species
using 15 of the mosaics. Simultaneously, spectral profiles were
built for 16 common species at the site using 25 of the mosaics. A
community level map displaying three main groups was produced for
the study site along with a phenology calendar which highlights key
dates for identifying various species. The results of this project
show that many species have a high amount of overlap in their
spectral signals following phenology, making differentiation of
individual species difficult when employing a pixel-based approach
alone.
Advisors/Committee Members: Dyer, James (Advisor).

► This thesis presents an approach to planning long distance soaring trajectories which exploit atmospheric energy to enable long distance, long duration flights by small and…
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▼ This thesis presents an approach to planning long
distance soaring trajectories which exploit atmospheric energy to
enable long distance, long duration flights by small and micro
unmanned aerial vehicles. It introduces the energy map, which
computes the minimum total energy required to reach the goal from
an arbitrary starting point while accounting for the effect of
arbitrary wind fields. The energy map provides the path to the goal
as a sequence of way points, the optimal speeds to fly for each
segment between way points and the heading required to fly along a
segment. Since the energy map is based on the minimum total energy
required to reach the goal it immediately answers the question of
existence of a feasible solution for a particular starting point
and initial total energy. The results obtained from energy map are
compared with other generic trajectory planners, namely A*. The A*
algorithm used uses a cost function which is the weighted sum of
energy required and remaining distance to goal. The effect of
varying the weight parameter on the flight paths is examined. The
energy expended along a path for varying weight is examined, and
the results are compared with a wavefront expansion planning
algorithm. The weight is selected based on maximum energy
utilization that is available from the atmosphere and minimizing
time to reach the goal. Optimal weight is selected based on
simulation results. Both the methods of path planning are now used
in real wind field data. Energy efficient routes are found in the
real wind field using both the methods.

The problem of stand-off tracking of a moving target using a quadrotor unmanned aerial vehicle (UAV) based on vision-sensing is investigated. A PID (Proportional-Integral-Derivative) controller…
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The problem of stand-off tracking of a moving target using a quadrotor unmanned aerial vehicle (UAV) based on vision-sensing is investigated. A PID (Proportional-Integral-Derivative) controller is implemented for attitude stabilization of the quadrotor. An LQG-based (Linear-Quadratic-Gaussian) control law is designed and implemented for position control of the quadrotor for a moving target tracking task. A novel vision-based estimation algorithm is developed, enabling estimation of quadrotor’s position, altitude and yaw relative to the target based on limited information about the target. Two image
processing algorithms are implemented and compared for the task of feature detection
and feature tracking in a series of images. Image processing algorithms are integrated
with quadrotor control and experiments are performed to validate proposed control and
estimation approaches.

The current research work analyzes the problems arising from the use of remotely piloted aircraft systems in Guarda Nacional Republicana protection and rescue mission. Its use implies a restriction of constitutionally protected rights of citizens, and this limitation lacks a valid check.
Therefore, the main objective of this study is to examine the feasibility of using unmanned aerial vehicle technology in Guarda Nacional Republicana protection and rescue mission. For this purpose, identifies a solution to the possible violation of rights, freedoms and guarantees of citizens; presents the advantages and disadvantages of the use of these vehicles and studies the suitability of this technology to develop protection and rescue missions, comparing it to other resources.
Regarding the methodology, the present work is based on the hypothetical-deductive method, drawing on interviews with the officers responsible for the area of protection and rescue in Guarda National Republicana, as well as collection of bibliographic references.
The information collected allow us to reach significant results that can determine the viability of using unmanned aerial vehicles in Guarda Nacional Republicana protection and rescue mission.

The Swedish Armed Forces today have problems during exercises with unidentified UAVs located over the exercise area. UAVs which can observe exercises and map infrastructure and abilities. This paper aims to investigate what capabilities a handheld laser pointer would create to counteract the problem of UAVs that are located over training areas or adjacent to protected area. The thought of examining handheld laser pointers is that handheld laser pointers are not large, heavy or energy-intensive, which would enable them to spread within the Armed Forces to all services. Experiments with different handheld laser pointers are performed to investigate the effects they give at a certain distance. Experiments are also carried out to check at which distances a specific UAV can perform reconnaissance assignments, as well as the ability to detect a UAV at various distances with and without aids. The experiments showed that if the observer is aware of the direction of the UAV, it is possible to detect it at 600m distance with aids and at 500m without. The experiments also showed that laser gives a glare effect at 75m which is not close to a UAV's possible reconnaissance distances.

► This thesis presents a new parallel 5 DOF robot called the H-Delta. The H- Delta adds 2 degrees of freedom (DOF) to the traditional Delta…
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▼ This thesis presents a new parallel 5 DOF robot called the H-Delta. The H-
Delta adds 2 degrees of freedom (DOF) to the traditional Delta robot in a novel
way, adding functionality and versatility. Importantly, the rotational DOF are
decoupled, independent of the translational movement.
This thesis begins by covering the necessary background the H-Delta is built
upon, and then describes the structure of the H-delta and how it improves upon
the state-of-the-art. The kinematic analysis of the H-Delta covers the inverse
kinematics, Jacobian matrix derivation, stiffness, and dexterity. To provide a
reference to an existing structure the H-Delta is compared to the benchmark
Stewart Platform.
A Dynamic analysis is performed by formulating the dynamic equations of
the H-Delta using the Lagrangian method. The results of the dynamic calcu-
lations are verified with a dynamic simulation which also acts as a test bed to
develop control systems.
A multi-objective optimization of the H-Delta is presented and using the in-
formation accrued to this point an initial prototype is designed and constructed
to verify the H-Delta structure.
With the knowledge of the strengths of the H-Delta gained from the analysis
and prototype, select applications are presented where the H-Delta best lends
its strengths to the application.
The H-Delta is mounted on a UAV to survey and interact with its surroun-
dings. The prototype can use an on-board camera to track the position of an
objective on the ground and center the gripper over it. When the UAV gets close
enough, the H-Delta reaches out and automatically retrieves the object. When
flying around, the H-Delta stabilizes the movement of the end effector, reducing
acceleration. The prototype movement is measured and the results show that
the end effector is accurate to within 3mm and the rotation is accurate within
0.5 degrees.
Advisors/Committee Members: Zhang, Dan.

► This thesis presents the design and build of tracking system for a quadrotor to chase a moving target based on computer vision in GPS-denied environment.…
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▼ This thesis presents the design and build of tracking system for a quadrotor to chase a moving target based on computer vision in GPS-denied environment. The camera is mounted at the bottom of the quadrotor and used to capture the image below the quadrotor. The image information is transmitted to computer via a video transmitter and receiver module. The target is detected by the color and contour-based detection algorithm. The desired pitch and roll angles are calculated from the position controller based on the relative position and velocity between the moving target and the quadrotor. Interface between PC and quadrotor is built by controlling the PWM signals of the transmitter for command transmission.
Three types of position controllers including PD controller, fuzzy controller and self-tuning PD controller based on fuzzy logic are designed and tested in the tracking tests. Results on the corresponding tracking performances are presented. Solutions to improving the tracking performance including the usage of optical sensor for velocity measurement and high-resolution camera for higher image quality are discussed in future work.
Advisors/Committee Members: Leonessa, Alexander (committeechair), Southward, Steve C. (committee member), Kochersberger, Kevin Bruce (committee member).

► The increased market for navigation, localization and mapping system has encouraged the research to dig deeper into these new and challenging areas. The remarkable…
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▼ The increased market for navigation, localization and mapping system has encouraged the research to dig deeper into these new and challenging areas. The remarkable development of computer soft- and hardware have also opened up many new doors. Things which more or less where impossible ten years ago are now reality. The possibilities of using a mathematical approach to compensate for the need of expensive sensors has been one of the main objectives in this thesis. Here you will find the basic principles of localization of indoor UAVs using particle filter (PF) and Octomaps, but also the procedures of implementing 2D scanmatching algorithms and quaternions. The performance of the algorithms is evaluated using a high precision motion capture system. The UAV which forms the basis for this thesis is equipped with a 2D laser and an inertial measurement unit (IMU). The results show that it is possible to perform localization in 2D with centimetre precision only by using information from a laser and a predefined Octomap.

Unmanned systems are becoming increasingly common in both the military and commercial market. Unmanned aerial vehicle, or in everyday language referred to as drones, is an aircraft that do not have a human pilot onboard. As the supply and demand of unmanned aircraft increases, manufacturers must put more focus on a complete system, meaning that the manufacturer can offer a complete system for unmanned aircraft. Therefore the need of accessories and peripherals are today as important as the unmanned aircraft. Unmanned Systems Group was founded…

► Under current regulations, Unmanned Aerial Vehicles (UAVs) are prohibited from operating in non- segregated airspace. The absence of a pilot is considered to be a…
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▼ Under current regulations, Unmanned Aerial Vehicles (UAVs) are prohibited from operating in non-
segregated airspace. The absence of a pilot is considered to be a potential hazard because the pilot is
responsible for the separation with other aircraft. In unmanned aviation the pilot, or operator, can never detect possible separation conflicts without the help of Detect, Sense and Avoid (DSA) systems. To make operation in civil airspace possible, there is a need for certified DSA systems. As of yet there are no certified systems available because the requirements for the certification are not yet developed. To help develop these requirements for these systems, research efforts experiment with these systems in both flight-tests and simulations.
One such a research effort is made by the Delft University of Technology (DUT) together with the
Netherlands Defence Academy (NLDA). They use a UAV ground station simulator to investigate the
‘Operator-in-the-Loop’ concept: the DSA system does not autonomously take action, but the operator is alerted when a possible threat is detected and asked to verify the threat and to decide what action to take. The research presented in this thesis is performed in order to increase the fidelity of the DSA models used in this simulator.
DSA systems use sensors to detect potential threats. This project focused on the simulation of the sensors used for detecting non-cooperative traffic. On the basis of a study of the literature the three most commonly used sensors were selected: radar, electro-optical (EO) and infrared (IR). After the subsystems and interfaces were defined the subsystems were designed in a two step iterative approach. The final radar simulation is a link-budget model and uses the Swerling algorithm for the detection calculation. The EO and the IR simulation system use a simplified geometric aircraft model to calculate the static and dynamic signature on the sensor image. The detection calculation is performed by weighing and combining the signatures and comparing them to a threshold value. All designed systems are verified with data obtained from other research projects.
Advisors/Committee Members: Theunissen, E..

► A Master Thesis Research has been undertaken with the goal of investigating the potential of micro gas turbines as propulsion system of choice for small…
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▼ A Master Thesis Research has been undertaken with the goal of investigating the potential of micro gas turbines as propulsion system of choice for small Unmanned Aerial Vehicle (UAV) used in civil applications. The UAV market is likely to develop great economic and technological importance on a near future because of the wide variety of applications and the added value related to the unmanned vehicles. In this regard, research focused on improving UAV capabilities is strictly related to UAV propulsion systems; as a matter of fact, aircraft performance is dependent on the mass of the power-plant and its specific fuel consumption since these can have a very significant effect on the reduction in size or increase in range of the UAV.
An Exploration Study is performed both in the fields of UAV technology and of Micro Gas Turbine technology. These two areas are covered in order to understand the possible advantages and limitations of micro gas turbine engines compared to alternative propulsion concepts (e.g. electric and reciprocating engines) when used for a specific application. After the identification of a significant Case Study, a conceptual design of a high-potential UAV micro gas turbine based propulsion system is performed. Prediction of scale effects is important within the framework of turbine conceptual design where the power output is varied in order to optimize the mission performance in which the turbine is integrated. To this end, engine cycle optimization using Gas turbine Simulation Program (GSP) is carried out. Furthermore, an "Aircraft Study" is performed in a correlated Master Thesis Project in which the aerodynamic and flight performance model of a baseline UAV is developed. After the model validation, results from the micro gas turbine model are integrated and the performance of the new UAV configuration is investigated.
The final engine configuration is a 77 kW dual shaft turboprop which is further implemented into the UAV platform redesigned accordingly to the reduced weight and improved performance. The mission model estimates for this configuration an endurance of 28.7 hours, with a range of 4419 km and a payload weight of 250 kg, with a significant fuel reduction of 12.5% compared to the original UAV configuration. The effect of power setting at cruise and the engine weight reduction allows the turboprop to arguably showcase overall better mission performance. As a result of the work carried out in this Master Thesis Project, a valuable tool for understanding the contribution of micro gas turbine integration into civil UAV has been developed.
Advisors/Committee Members: Visser, W.P.J..

Marcellan, A. (2015). An exploration into the potential of microturbine based propulsion systems for civil Unmanned Aerial Vehicles:. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:db9e8daf-dede-4915-9425-df4bc9706c12

Marcellan A. An exploration into the potential of microturbine based propulsion systems for civil Unmanned Aerial Vehicles:. [Internet] [Masters thesis]. Delft University of Technology; 2015. [cited 2019 May 25].
Available from: http://resolver.tudelft.nl/uuid:db9e8daf-dede-4915-9425-df4bc9706c12.

Council of Science Editors:

Marcellan A. An exploration into the potential of microturbine based propulsion systems for civil Unmanned Aerial Vehicles:. [Masters Thesis]. Delft University of Technology; 2015. Available from: http://resolver.tudelft.nl/uuid:db9e8daf-dede-4915-9425-df4bc9706c12

▼ Unmanned Aerial Systems (UASs) are emerging in the industrial, consumer and re- search domains. A key challenge for UAS communications is overcoming slow and unreliable wireless connectivity by achieving high link utilization on multiple radio interfaces. We have developed and implemented a peer-to-peer communication framework, based on Dispersy and Libswift, that allows multihomed (connected to multiple networks) UASs to utilize all available links.
In our experiments we address four use cases. The first use case describes data transfer from an Unmanned Aerial Vehicle (UAV) to a ground station, where the UAV starts and finishes out of communicative reach. The second use case expands on the first by utilizing two links on both entities. The third use case focuses on a UAV relaying communication between two ground stations that are incapable of communicating directly. The final use case has two ground stations in contact with each other, that successively receive data from a UAV and immediately share it.
The results show low data transfer throughput in general. Multi-link utilization is functional, but the data transfer rate is 32% lower for two links than for a single link. Data duplication rates are significantly higher for wireless links than for wired links, and more than double when utilizing two links instead of one. Libswift is responsible for the data transfer and its reported problem with long latency is suggested to be the primary cause for these disappointing results. Thus, future implementations should work with an improved version of Libswift.
We consider the effective utilization of multiple links combined with peer-to-peer systems to have real world use cases for UAVs and mobile devices in general. Therefore, we recommend future research to focus on deployable applications to that end.
Advisors/Committee Members: Pouwelse, J..

► Delta wing aircraft are becoming more commonplace due to the increasing numbers of unmanned aerial vehicles (UAV) which favour designs capable of producing large amounts…
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▼ Delta wing aircraft are becoming more commonplace due to the increasing numbers of unmanned aerial vehicles (UAV) which favour designs capable of producing large amounts of lift with a small, transportable wing span. A recent prototype UAV design, the 1303 UCAV, is similar to many existing UAV designs, with a moderate sweep angle of 47˚. However it undergoes a problematic onset of pitch break as the angle of attack is increased.
In this thesis, computational fluid dynamics (CFD) is used to examine the
Flow over the 1303 UCAV and better understand the cause of the onset of pitch break. The CFD modelling was validated against published wind tunnel data for the 1303 UCAV. The potential to control a UAV using geometric morphing instead of, or in addition to, conventional control surfaces was investigated by simulating the maneuvering moments produces by a range of different geometric morphs.
CFD modelling was also used to simulate the flow over a higher sweep angle wing with a sweep of 65˚ at a moderate angle of attack of 10˚. At this angle of attack the flow was demonstrated to be relatively stable, with very little unsteadiness, and the model was validated against published experimental data.
The impact of sweep angle on the vortex structures was investigated by simulating a wide range of sweep angles, and the flow was demonstrated to transition between two different structures when the sweep angle was between 50˚ and 55˚.

► This thesis assesses the feasibility of applying coverage model to the problem of using unmanned aerial vehicles (UAVs) for aerial surveillances. The purpose of aerial…
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▼ This thesis assesses the feasibility of applying coverage model to the problem of using unmanned aerial vehicles (UAVs) for aerial surveillances. The purpose of aerial surveillance is using sensors to cover the task area to obtain the information regarding to this area, such as environmental study. Comparing to static sensors, business purposes UAVs have higher mobility. Since static sensors have limited sensing range, it is not possible to use them to cover the task area. UAVs with sensors onboard can be used for surveillance and save the data to obtain more detailed information of the task area. The data retrieved by the sensors can be used for developing autonomous control algorithms for navigation of the UAV. However, there are some inevitable factors that shortens the flight time of the UAV. For example, considering the maximum payload of the UAV, the battery of UAV can usually last at most 30 minutes since it cannot be very large. It is very important to improve the efficiency of UAV surveillance by pre-designing the flight path for one UAVs or deployment positions for multiple UAVs.
Advisors/Committee Members: Chen, Xiang.